Power end: The frame is of welded steel-plate construction and internal stress is eliminated after being welded. It has high strength, good rigidity and light weight. Integral herringbone gear drive is adopted for smooth running, high efficiency and long operating life. The crank shaft is alloy steel casting. Double-deck sealing is adopted in intermediate pull rod with sound sealing effect. The power end adopts the lubricating method of forced lubrication combined with splash lubrication.